The following relates generally to wireless communication, and more specifically to scheduling request (SR) transmission for directional beam access.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems.
In some examples, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipment (UEs). In a Long-Term Evolution (LTE) or LTE-Advanced (LTE-A) network, a set of one or more base stations may define an eNodeB (eNB). In other examples (e.g., in a next generation new radio (NR) or 5G network), a wireless multiple-access communication system may include a number of smart radio heads (RHs) in communication with a number of access node controllers (ANCs), where a set of one or more RHs, in communication with an ANC, defines a base station (e.g., an eNB). A base station may communicate with a set of UEs on downlink (DL) channels (e.g., for transmissions from a base station to a UE) and uplink (UL) channels (e.g., for transmissions from a UE to a base station).
In some examples, a wireless network may operate in millimeter wave (mmW) spectrum. Using mmW spectrum may result in additional attenuation, which may impact the link budget of the communications. A UE and a base station operating in mmW spectrum may utilize beamforming techniques to increase the strength of wireless signals in particular directions to address the additional attenuation. However, because of the directional nature of beamformed transmissions, a base station may miss or otherwise fail to decode a message (e.g., a SR) sent from a UE unless there is coordination of the directional transmission and reception of signals between the base station and the UE.